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Chapter 2
ENERGY &
MATTER
Warm-Up
 With the people at your table discuss what “matter”
means; please give 3 examples.
 Can you think of any examples where matter is not
present?
3 States of Matter [Actually 4 States]
 Solid-definite shape & volume,
maintains shape without a
container.
 Liquid-definite volume but
indefinite shape, takes the
shape of its container but does
not fill.
 Gas-indefinite shape & volume,
fills any container placed in.
 Plasma-highly ionized form of
gas that exists at high temps.
(surface of the sun)
Physical Characteristics
 Physical Changes-These are
observed or tested without changing the
substance.
Physical Properties of Matter
 Extensive Properties- dependent on the
quantity of matter. (mass, volume, shape)
 Intensive Properties-Not dependent on
the size of the sample. (melting point,
boiling point, density)
Chemical Characteristics
 Chemical Properties-How a substance reacts with
other substances. This is observed in chemical
reactions.
 Chemical Change-When a substance is converted
into a new substance. All properties and
characteristics will change!
 Format: Reactants
(start)

Products
(yields)
(ending)
Inferences vs. Observations
 Observation: You use one or more of your five
senses to know or determine something.
Inference: You make an explanation for the
observation.
Example:
You see steam rising off of a cup of
coffee. (Observation)
The coffee is hot. (Inference)
Indicators of Chemical Change
 1. Heat and/or light.
 2. Evolution of a gas (not from boiling)
 3. Production of a precipitate (ppt.) (solid
but not from freezing)
 4. Color change
Learning Targets
1) Compare physical and chemical properties of
matter.
2) Explain the differences between elements,
compounds, and mixtures.
3) Explain the difference between homogeneous and
heterogeneous mixtures, and techniques to
separate them.
Pure Substances
 Elements & Compounds
 Unique
chemical and physical
properties
 The
same composition
 They
can not be separated without
changing properties.
Element
 A substance that can not be broken down
into another substance by chemical means.
 The smallest part is an atom
 There are approximately 90 naturally
occurring elements.
Elements
 Earth’s Crust:






Oxygen 49.5%
Silicon 25.7%
Other 9.2%
Aluminum 7.5%
Iron 4.7%
Calcium 3.4%
 Human Body




Oxygen 65%
Carbon 18%
Hydrogen 10%
Other 7%
Compound
 A substance that can be broken down
into another substance by chemical
means.
 The smallest part is a molecule or ion.
Mixtures
 Mixture-Physical combination of
2 or more substances.
 2 Classifications:
Heterogeneous-different
composition present
[examples: sand, granite, milk of
magnesia]

Homogeneous-same composition
present throughout. They are
referred as solutions.
[examples: salt water, Gatorade, coffee]

Separation of Mixtures
 separate mixtures based on different physical
properties of the components
Different Physical Property
Technique
Boiling Point
Distillation
State of Matter (solid/liquid/gas) Filtration/Decanting
Dissolves in water
Evaporation
Distillation
Filtration
Evaporation
Liquid vaporizes leaving less volatile liquid or
solid.
Learning Target
 List the different types of energy.
Learning Targets
 Know and apply the 3 basic forms of energy.
What is Energy?
 The capacity to do work or produce heat.
Law of Conservation of Energy
 Energy can neither be created nor
destroyed in any chemical or
physical process. It can be
converted from one form to
another.
2-1 Energy
•
Energy is classified into three main forms
•
Radiant
•
Kinetic &
•
Potential
Radiant Energy
This is energy from the Sun
which is the result of nuclear
fusion
http://interestingenergyfacts.blogspot.com/
2010/04/nuclear-fusion-facts.html
Kinetic Energy
This is the energy carried by objects in motion,
like a locomotive.
Kinetic Energy includes:
1. Mechanical energy carried by the
moving parts of a machine
2. Thermal Energy of the random
internal motion of particles in all substances
(This is what is measured with temperature)
Potential Energy
This is the energy possessed by objects because
of the position or the arrangement of their
particles
In essence it is stored energy.
Gravitational Potential Energy
•
•
The kind of energy carried by water before it
falls through the spillway of a hydroelectric
dam is called gravitational potential
energy.
Gravity is responsible for converting the
potential energy of the water into kinetic
energy , which is then able to do work
Other forms of Potential Energy
Electrical Energy
is the energy that exists when objects
with different electrical charges are separated.
Batteries operate on this principle.
•
Other forms of Potential Energy
Chemical Energy
 This is the energy which exists in some
substances because of the arrangement
of their particles.
 Fuels and food contain chemical
potential energy
Learning Target – 10/8/13
Know the energy units (Calories,
calories, kilojoules, joules), and how to
convert from one unit to another.
What unit of energy do you
personally consume everyday?
Calorie (cal) [older unit]
 The amount of energy required to raise the
temperature of 1 gram of water by 1 degree
Celsius.
 Example #1: How much energy is
required to raise 31.0 g of water from
10°C to 25°C?
Energy stored in food is often given
a unit that is related to the calorie.
1 Calorie (Cal) or 1 kilocalorie = 1000cal
James Joule
 English scientist in the mid-1800’s
 Known as the father of
thermodynamics
 He found that changes produced
by heating a substance could also
be produced by mechanical energy
 He discovered the relationship
between mechanical energy and
heat energy and formed the basis
for the Law of Conservation of
Energy
The SI Unit of energy is the
Joule (J)
Joule (J) in the long form is kg.m2/s2
4.184J = 1 cal
4.184 kJ = 1kcal or 1Cal
1 kJ = 1000 J
1 Cal or kcal = 1000 cal
1cal =4.184 joules
chocolate bar=200 Cal
200Cal x 4.184 kJ/Cal=
Energy in one chocolate bar= 836.8kJ
How many Joules?
How many calories?
Learning Target
 Know the difference between Fahrenheit, Celsius,
and Kelvin temperature scales and how to convert
from one scale to another.
 Explain what is meant by Absolute Zero.
What is the difference between
heat and temperature?
Thermal Energy (Heat) vs.
Temperature
 Thermal Energy = sum total of all
the KE of the particles in a sample.
 Temperature = measure of the
average KE of the particles
Temperature
Kelvin
Degrees Celsius
Peak emittance wavelength[65]
of black-body radiation
0K
−273.15 °C
cannot be defined
100 pK
−273.149999999900 °C
29,000 km
450 pK
−273.14999999955 °C
6,400 km
0.001 K
−273.149 °C
273.16 K
0.01 °C
Water's boiling point[A]
373.1339 K
99.9839 °C
Incandescent lamp[B]
2500 K
≈2,200 °C
Sun's visible surface[D][69]
5,778 K
5,505 °C
28 kK
28,000 °C
16 MK
16 million °C
350 MK
350 million °C
2 GK
2 billion °C
3 GK
3 billion °C
350 GK
350 billion °C
1 TK
1 trillion °C
10 TK
10 trillion °C
1.417×1032 K
1.417×1032 °C
Absolute zero
(precisely by definition)
Coldest temperature
achieved[66]
Coldest Bose–Einstein
condensate[67]
One millikelvin
(precisely by definition)
Water's triple point
(precisely by definition)
Lightning bolt's
channel[E]
Sun's core[E]
Thermonuclear weapon
(peak temperature)[E][70]
Sandia National Labs'
Z machine[E][71]
Core of a high-mass
star on its last day[E][72]
Merging binary neutron
star system[E][73]
Relativistic Heavy
Ion Collider[E][74]
CERN's proton vs
nucleus collisions[E][75]
Universe 5.391×10−44 s
after the Big Bang[E]
2.89777 m
(radio, FM band)[68]
10,608.3 nm
(long wavelength I.R.)
7,766.03 nm
(mid wavelength I.R.)
1,160 nm
(near infrared)[C]
501.5 nm
(green-blue light)
100 nm
(far ultraviolet light)
0.18 nm (X-rays)
8.3×10−3 nm
(gamma rays)
1.4×10−3 nm
(gamma rays)[F]
1×10−3 nm
(gamma rays)
8×10−6 nm
(gamma rays)
3×10−6 nm
(gamma rays)
3×10−7 nm
(gamma rays)
1.616×10−27 nm
(Planck Length)[76]
Thermometer
 The modern
thermometer used in
our class is filled with
colored alcohol.
Fahrenheit Scale
 Daniel Fahrenheit developed the first alcohol
thermomter in 1709 and the mercury thermometer
in 1714
 He divided the freezing and boiling points of water
into 180 degrees. 32° F was freezing of water and
212° F was the boiling piont.
 0° F was based on the temperature of water, ice and
salt mixture.
Celsius Scale
 In 1742 Anders Celsius took 0° C for freezing of
water and 100° C for the boiling point of water.
 He dividing these points into equal scales.
 Often referred to as the “centrigrade” scale which
mean “divided into 100 degrees”
Kelvin
 Lord Kelvin used the same scale as Celsius to invent
the Kelvin scale in 1848.
 He developed the theoretical idea of absolute zero
and this became 0 K.
The Celsius Temperature Scale
 The freezing point of
pure water at sea
level is 0º C, 32°F,
273.15 K.
 The boiling point of
pure water at sea
level is 100ºC, 212°F,
373.15 K.
Kelvin Temperature Scale
 SI Unit for temperature is Kelvin (K).
 The degree unit is not used in Kelvin (K),
The Difference between Kelvin and Celsius
 The main difference is the
location of the zero point.
 The zero point for kelvin is
called absolute zero.
 Absolute zero is equal to
-273º C or 0K.
 Absolute zero is the point at
which the motion of particles
of matter has completely
stopped.
Converting Kelvin and Celsius
 ºC = K – 273
 K = ºC + 273
Convert 50. K to the Celsius scale
Converting Fahrenheit to Celsius
 ºC = (ºF – 32) x 5/9
 Convert 67°F to °C
 ºC = (67º – 32) x 5/9 = 19.4 ºC
Converting Celsius to Fahrenheit
 ºF = (9/5 x ºC) + 32
 Convert -14 ºC to ºF
 ºF = (9/5 x -14º) + 32 = 6.8ºF
Learning Target
1) Name and describe the 4 states of matter
2) Describe the differences between a physical change
and chemical change.
Kinetic Energy (KE)
 KE = ½ mv2
 KE = kinetic energy
Unit
J = Joule (kg.m2/s2)
 m = mass
kg
 v = velocity
m/sec
Calculate the KE of a 70kg
man walking at 2.5m/s.
Potential Energy (PE)
 Stored energy
 Gravitational Potential Energy –energy due to
position
 PE = mgh
Units
 PE = potential energy
 m = mass
J= Joule
kg
 g = force of gravity
Earth = 9.8 m/sec2
•
 h = height
(CONSTANT)
meter
What is the gravitational potential energy of
a 2 kg ball at rest on a window sill, 40m up
from the pavement?
PE=m g h
m=2kg
h= 40m
g=9.8m/s2
PE = 2kg x 40m x 9 .8m/s2
PE = 784 Joules
WARM-UP PROBLEM
 Determine the kinetic energy for a
400 g ball traveling at 3.0 km/min.
(Remember to convert g to kg and
km/min to m/s.)
See sample problem #4
 What is the minimum height the
ball would need to be dropped from
to achieve this velocity before
impact with the ground?